| 1 | // RUN: %clang_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s |
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| 2 | // Regression test for |
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| 3 | // https://groups.google.com/d/msg/thread-sanitizer/e_zB9gYqFHM/DmAiTsrLAwAJ |
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| 4 | // pthread_atfork() callback triggers a data race and we deadlocked |
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| 5 | // on the report_mtx as we lock it around fork. |
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| 6 | #include "test.h" |
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| 7 | #include <sys/types.h> |
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| 8 | #include <sys/wait.h> |
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| 9 | #include <errno.h> |
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| 10 | |
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| 11 | int glob = 0; |
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| 12 | |
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| 13 | void *worker(void *unused) { |
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| 14 | glob++; |
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| 15 | barrier_wait(barrier: &barrier); |
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| 16 | return NULL; |
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| 17 | } |
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| 18 | |
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| 19 | void atfork() { |
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| 20 | glob++; |
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| 21 | } |
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| 22 | |
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| 23 | int main() { |
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| 24 | barrier_init(barrier: &barrier, count: 2); |
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| 25 | pthread_atfork(prepare: atfork, parent: atfork, child: atfork); |
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| 26 | pthread_t t; |
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| 27 | pthread_create(newthread: &t, NULL, start_routine: worker, NULL); |
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| 28 | barrier_wait(barrier: &barrier); |
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| 29 | pid_t pid = fork(); |
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| 30 | if (pid < 0) { |
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| 31 | fprintf(stderr, format: "fork failed: %d\n" , errno); |
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| 32 | return 1; |
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| 33 | } |
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| 34 | if (pid == 0) { |
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| 35 | fprintf(stderr, format: "CHILD\n" ); |
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| 36 | return 0; |
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| 37 | } |
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| 38 | if (pid != waitpid(pid: pid, NULL, options: 0)) { |
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| 39 | fprintf(stderr, format: "waitpid failed: %d\n" , errno); |
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| 40 | return 1; |
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| 41 | } |
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| 42 | pthread_join(th: t, NULL); |
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| 43 | fprintf(stderr, format: "PARENT\n" ); |
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| 44 | return 0; |
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| 45 | } |
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| 46 | |
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| 47 | // CHECK: ThreadSanitizer: data race |
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| 48 | // CHECK: Write of size 4 |
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| 49 | // CHECK: #0 atfork |
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| 50 | // CHECK: Previous write of size 4 |
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| 51 | // CHECK: #0 worker |
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| 52 | // CHECK: CHILD |
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| 53 | // CHECK: PARENT |
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| 54 | |
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